Improvement in grist-mills



EDWARD HAHRiSON.

Improvement in'Grst MHs'.

Patented Jan. 9, 1872.

EDWARD YHARRIsON, or New RAVEN, CONNECTICUT.

IMPROVEMENT IN GRIST'MILLS.

Specification forming part of Letters Patent No. 122,605, dated January9, 1872.

' To all whom it may concern:

Be it known that I, EDWARD HARRISON, of New Haven, in the county of NewHaven and State of Connecticut, have invented a new Improvement inGrist-Mills; and I do hereby declare the following, when taken inconnection with the accompanying drawing and the letters of referencemarked thereon, to be a full, clear, and exact description of the same,and which said drawing constitutes part of this specification andrepresents, in-

Figure 1, a side view; Fig. 2, a longitudinal central section, and inFig. 3 a'transverse section.

This invention relates to an improvement in combined grinding andbolt-mills, the object being to combine with the mill a revolving bolt,and so that the stones will discharge into the bolt around theircircumference-that is to say, so that the runner-stone shall revolvedirectly within the bolt; and the invention consists chieiiy in socombining the bed and runner-stone of a grist-mill with a revolving boltthat the runner-stone will revolve directly within the bolt, as morefully hereinafter set forth.

A is the bolt-case, to one head, B, of which the mill is attached. C isthe bed-stone case, within which the bed-stone D is arranged in theusual manner for the mill known as the Harrison mill, and embodying theimprovements in the mill for which I filed an application for patent onor about November 29, 1871. E is the driving-shaft or mill-spindle,supported in a bearing, F, ruiming through into the runner-stone, drivenby a pulley, G, in substantially the manner as in the mill beforereferred to. Upon the shaft E the runner-case H is iixed, and so as torevolve therewith. Centrally in the runner-case I form a sleeve, l,fitting closely the bearing F ofthe shaft E, so as to form a compoundbearing for the runnerstone, or a bearing in addition to F formed on thebed-stone case. Lis the feed-spout; M the hopper, applied and Operatingas in the mill before `referred to. In this construction therunner-stone is adjusted by a nut, a, on the bed-stone case, which bearsagainst the pulley, and by the turning of this nut-the pulley being xedto the shaft-the runner-stone may be drawn closer to the bed-stone orpermitted to run further from it. A second head, N, similar to the headB, is arranged distant from the head B the length required for the bolt,and between the two heads is tted with a case, A, with a longitudinalopenin g, P. Vithin this case the bolt is arranged, consisting of tworings, d e, of angular form, as seen in transverse section, Fig. 2, sothat the one,

takes a bearing withina flange, f, within the head B, the other, e,within a similar flange, g, within the head N. These rings are joinedtogether by longitudinal bars B, which, by preference, are made of wood,on account of its weight. The bolt is made to revolve by means of aninternal gear, h, on the ring 0l through a pinion, S, in the shaft T,driven by a pulley, U, to give the bolt the necessary velocity. The boltoutside the bars B is covered with bolt-cloth, as denoted by brokenlines in Figs. 2 and 3, a little less in diameter than the shell, andoutside these bars, over the bolt-cloth, sweeps or bars W are applied soas to run in close proximity to the shell; hence when the mill is set inmotion, and the bolt with it--the bolt by preference being drivendirectly from the mill-shaft-the meal is driven with great force againstthe bolt-cloth and thefinest portion will pass directly through thebolt-cloth into the space between it and the shell. Other portions, thebolt being inclined, naturally tend to work from the stones toward theother end of the bolt, and different grades or neness of meal passthrough the bolt at different sections, leaving only the bran at theeXtreme end within the mill. The bars B carry up the meal until it fallstherefrom back onto the bolt-cloth to facilitate the sifting. The flourwhich passes through the boltcloth is taken by the sweeps W and carriedup to the opening P and there discharged, provision being made for thedifferent grades. The bran which is still within the bolt is continuallycarried up by the bars B until it reaches the extreme end and is theredischarged inside the bolt bythe bars B into the dischargespout Y,thence passing out` through the conductor Z, the said vspout beingdenoted in broken lines, Fig.` 3. By preference I make the head Nremovable, so that by taking it from the case the hopper may be drawndirectly out, if for any purpose this should be FFICR.'

required. By applying power to drive the bolt to one of the rings of thebolt I avoid the central shaft, which is usually employed, and thenecessary arms or spokes to connect the shaft to the rings or heads. Tostrengthen the bolt to prevent this manner of driving from twisting thebolt I extend from one bar to the next, and so on around the bolt,brace-rods n, (see Fig. 2,) forming, as it were, a truss for theinternal support of the bolt.

I claim as my invention- I. The arrangement of the bed and runnerstoneof a grist-mill within a revolving bolt, substantially as described, sothat the runnerstone discharges the meal around its periphery directlyinto the bolt.

2. In combination with the bearing F, formed upon the bed-stone case Cof the mill, I claim the sleeve I formed on the runner-stone casesurrounding said bearing` F, through which the shaft E passes to therunner-stone case, substantially as set forth.

3. In combination with the mill and revolvingbolt, constructedsubstantially as described, 1 claim the gear h on one head of the boitand the pinion S Working in the said gear to cause the said bolt torevolve, substantially as specied.

4. In a bolt, consisting ofthe heads e h, bars R, bolt-cloth and case A,I claim the sWeepsW Within the case to carry the ilour to thedischargespout P, in the manner and for the purpose substantially as setforth.

5. In combination With the subject-matter of the fourth clause ofclaims, I claim the diag onal braces n within the bolt, as and for thepurpose specified..

6. In combination with the subject-matter of the fourth clause ofclaims, I claim the internal discharge Y Z, as and for the purpose setforth.

EDWARD HARRISON.

Witnesses A. J TIBBI'rs, J. H. SHUMWAY.

